Control mechanism



E. WILLIAMS.

CONTROL MECHANISM.

APPLICATIVON FILED JAN. 28. 1920.

Patented Sept. 21, 1920'.

warren s'rares smear OFFICE. 7

EDWARD WILLIAMS, OF BIRMINGHAM, ENGLAND.

CONTROL MECHANISM.

a To all whom it may concern:

Be it known that I, EDWARD WILLIAMS, a subject of the King of Great Britain and Ireland, residing at 17 Sandon road, Edgbaston, in the city of Birmingham, England, have invented certain new and useful Improvements Relating to Control Mechanisms, of which the following is a specification.

A well known device for controlling mechanical movements consists of a rotary disk provided on its periphery with striking pieces which produce intermittent movements of a lever, tappet or the like. For example, the disk may be fitted with a pair of striking pieces for actuating a lever. One striking piece moves the lever in one direction and the other, produces the opposite movement. The lever may be utilized to operate in turn each of a pair of clutches or a reversing or other gear change mechanism. Sometimes it is desired to arrange a relatively large number of striking pieces on the disk and this usually involves one or more of the following difliculties, namely, the angular distance between the pieces is inconveniently small, the diameter of the disk is inconveniently large, or the speed of rotation of the disk is inconveniently slow. The object of the present invention is to provide an improved control mechanism whereby these difficulties are avoided. By my invention any number of striking pieces can be arranged at comparatively wide angular distances apart on a peripheral surface which can be of small diameter and can be driven at convenient speeds.

The invention comprises the use of a drum having striking pieces disposed spirally around its periphery and which in addition to a rotary motion receives an axial movement for the purpose of bringing successive striking pieces into operation.

The accompanying drawing illustrates diagrammatically one manner of carrying the invention into effect.

In applying the invention as shown to a control mechanism in which the striking pieces a are adapted to produce opposite intermittent movements of a lever 72 for actuating a clutch or other device, a drum 0 is secured to a driving shaft d which has a screw thread formed on a portion of its length and is capable of moving endwise. This movement may occur against the action of a spring 6. The screw thread can be Specification of Letters Patent. Patented Sept, 21, 1920, Application filed January 28, 1920. Serial No. 354,756.

engaged by a stationary half-nut 7 adapted to be moved into and out of operative connection with the thread. Around a spiral path 9 on the'drum of the same pitch as the shaft thread the striking pieces a are secured at suitable angular intervals. For convenience in locating the said pieces a spiral dovetail or other slot may be formed around the drum, clamping screws it being provided for securing the striking pieces in position. which would be used is two, but usually a considerable number would be provided as it is when a large number of pieces are required that-the invention is particularly advantageous- In action the nut f is engaged with the shaft all so that'the drum 0 receives an axial The smallest number of pieces- 7 or endwise movement in addition to. the rotary movement. During this movement the spring shaft. the desired rocking movements of the lever b. At the end of each complete cycle of operation the nut is disengaged and the shaft restored to its initial position. When a spring is used the return is effected by the spring. Any other convenient means may be employed for returning the shaft and drum.

The invention is not limited to any particular means actuated by the striking pieces. Instead of a lever they may operate a sliding tappet, or a ratchet and pawl, or they may be adapted to control electric circuits.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is In controlling mechanisms, the combination comprising a rotatable and axially movable drum, striking pieces disposed spirally aroundthe drum, a screw threaded driving for imparting a reverse axial movement'to the drum and shaft after disengagement of the latter by the said engaging means, substantially as described.

In testimony whereof I have name to this specification.

EDWARD WILLIAMS.

signed my when used) is compressed by the 7 uccessive striking pieces produce 

